Section 27-566
§ 27-566 Floor live loads. The uniform live load to be used for design
shall be the basic value established in reference standard RS 9-2
multiplied by the percentages given in subdivisions (a) through (d) of
this section.
(a) Except as provided in subdivisions (b), (c), and (d), the
percentages in table 9-1 shall apply. Contributory areas shall be
computed in accordance with section 27-567 of this article.
(b) No live load reduction shall be permitted for the following:
members and connections (other than columns, piers, and walls)
supporting floor areas used for storage (including warehouses, library
stacks, and record storage); areas used for parking of vehicles; and
areas used as place of assembly, for manufacturing, and for retail or
wholesale sales. For columns, piers, and walls supporting such floor
areas the maximum live load reduction shall be twenty per cent.
(c) No live load reduction shall be permitted for calculating shear
stresses at the heads of column in flat slab or flat plate construction.
(d) In lieu of the percentages given in table 9-1, the live load
reductions for columns, piers and walls may be taken as fifteen per cent
of the live load on the top floor, increased successively at the rate of
five per cent on each successive lower floor, with a maximum reduction
of fifty per cent; and for girders supporting two hundred square feet or
more of floor area, the live load reduction may be taken as fifteen per
cent. The limitations of subdivisions (b), (c) and (d) of this section
shall apply.
TABLE 9-1 Percentage of Live Load*
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Ratio of Live Load to Dead Load*
Contributory Area 0.625 or less 1 2 or More
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149 or less 100 100 100
150-299 80 85 85
300-449 60 70 75
450-599 50 60 70
600 or more 40 55 65
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Note:
* For intermediate values of live load/dead load, the applicable
percentages of live load may be interpolated.
Section 27-567
§ 27-567 Contributory floor areas. For purposes of computing live load
reduction, contributory floor areas shall be determined as follows:
(a) For the design of one-way and two-way slabs: the product of the
shorter span length and a width equal to one-half the shorter span
length. Ribbed slabs shall be considered as though the slabs were solid.
(b) For the design of slabs in flat plate or flat slab construction:
one-half the area of the panel.
(c) For the design of columns and girders or trusses framing into
columns: the loaded area directly supported by the column, girder, or
truss. For columns supporting more than one floor, the loaded area shall
be the cumulative total area of all the floors that are supported.
(d) For the design of joists and similar multiple members framing into
girders or trusses, or minor framing around openings: twice the loaded
area directly supported but not more than the area of the panel in which
the framing occurs.
Section 27-568
§ 27-568 Foundations and column supports. The live load to be
supported by the foundation or by trusses or girders that support
columns shall be the total column reaction reduced as provided in
section 27-566 and section 27-567 of this article.
To the extent possible under law, Friends of Devin Balkind for Public Advocate has waived all copyright and related or neighboring rights to New York City Administrative Code. This work is published from: United States.
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